The major use of the Clinical Research Center for Children at the Children's Hospital of Buffalo can be subdivided between pharmacologic investigations and endocrine studies. Thus, this Clinical Research Center is unique in that pediatric clinical pharmacology has been, and continues to be, an important activity of the Center. Pharmacokinetic studies of a number of drug substrates in various disease states are being carried out. These include the disposition of theophylline in children with asthma and correlation with bronchodilating effect. Investigation of dicloxacillin and methacillin absorption, distribution and elimination in patients with cystic fibrosis is in progress. These same patients are being studied with respect to salicylate and antipyrine metabolism. A number of drug substrates are being studied in patients with renal disease in an attempt to estimate therapeutic doses from renal functional impairment. Studies are also being undertaken in these patients of drug disposition into peritoneal dialysis fluid. Digoxin pharmacokinetics is being evaluated in young infants, both during digitalization and during maintenance therapy. Endocrine studies include a major focus upon growth hormone secretion and its regulation in a number of disease states manifested by dwarfism. Studies of hormone control of carbohydrate metabolism in brittle diabetics are also in progress.